Wheels and tires....

[longbed67]

I know this has been talked about a 50+ times and I have read 42 listings on tire and rim size in this forum already so I am not coming here posting without having read first.... I am going to be putting Showwheels --Polished Streeter model rim on the truck. I am debating the size of rim and tire. A little more info on the truck.... I am about to start installing D2600 air bags all 4 corners and will be running 2.5" drop spindles up front. I am NOT looking to lay frame or even close and will be running stock control arms, I haven't decided whether to c notch the rear yet or not. I was debating which combination will be the best, as well as whether they will clear the stock fenders or not. Any thoughts, data, pics, facts, or otherwise is much appreciated. My first choice is Combo 1 but I am concerned with them fitting in the wheel wells without rub. Thanks in advance.

Combo 1
General G Max AS-03 tires
Front: 18x8 (4.5" backspace, 0 offset), 245/45ZR18 which are 26.7" tall
Rear: 20x10 (5.5" backspace, 0 offset) 275/40ZR20 which are 28.7" tall

Combo 2
General G Max AS-03 tires
Front: 18x8 (4.5" backspace, 0 offset), 245/45ZR18 which are 26.7" tall
Rear: 18x9 (5.25" backspace, +6 offset) 255/45ZR18 which are 27" tall

Combo 3
General G Max AS-03 tires
Front 17x8 (4.5" backspace, 0 offset) 245/50ZR17 which are 26.3" tall
Rear: 18x9 (5.25" backspace, +6 offset) 255/45ZR18 which are 27" tall